A conference on interactions between blood and the pulmonary circulation will be held in Colorado from September 6-10, 2000. This is the tenth in a series of conferences on the pulmonary circulation. The proceedings of prior meetings have appeared in Chest (1995), the American Review of Respiratory Disease (1987 and 1989) and as books published by Futura Publishing Co., and Plenum Press. The conference will have a total of 25 speakers (all of whom have already agreed to attend) and 8 chairs. An additional 50-60 participants are anticipated, who will be encouraged to bring posters. Equal time is given to presentations and discussion. Each session will be summarized by the chair, who will also lead a poster discussion on the same topic. The objectives of the conference are: 1) to determine the factors controlling erythrocyte adhesion in the pulmonary circulation, especially in sickle cell disease and to examine interactions between erythrocytes and leukocytes; 2) to analyze the role of platelets in development of pulmonary hypertension; 3) to elucidate mechanisms by which leukocytes and inflammation are involved in lung injury and pulmonary hypertension; and, 4) to define the contribution of coagulation and fibrinolytic defects in the pathogenesis of different forms of pulmonary hypertension. The information developed at this conference will be disseminated as a book, rather than a journal, because the presentations are in many cases the summation of research experience rather than the results of circumscribed experiments which could be published as original data. This application requests funding for printing the program, mailing costs, partial reimbursement of the airfares for domestic speakers, and the rental of poster boards. This is the tenth Pulmonary Circulation conference at the same venue, so the logistics of organizing the meeting will be relatively easy. Both the site and format of the conference have proved successful in the earlier meetings.